Sheet surfacing



March.19, 1929. HARRINGTON 1,705,918

' SHEET SURFACING Filed Aug. 16, 1927 4 Sheets-Sheet l lNVENTOR March19, 1929. A. HARRINGTON SHEET SURFACING Filed Aug. 16, 1927 4Sheets-Sheet INVBNTOR March 19, 1929. A. L. HARRINGTON 1,705,913

SHEET SURFACING Filed Aug. 16, 1927 4 Sheets-Sheet 5 INVENTOR 6:iiii:rwa A E; 555mm;EEEQEHEEEEEHE W f z Patented Mar. 19, 1929.

UNITED STATES.

PATENT o FIcE- ALFRED L HARRINGTON, OF nossLYN' FARMS, PENNSYLVANIA,ASSIGNOR To PITTS- BURGH PLATE eL sscomrANY, A coE-roEATIoN orPENNSYLVANIA.

SHEET su'ma'AcIim.

The invention relates tosheet surfacing.

I a series of polishing machines, as set forth in my Patent No.1,671,718, dated May 16, 1928, and it will be understood that the singlemachine here shown and" described is only one of a series,

tral station, and that the other machines of the system are similarlyconstructed. and controlled. The machine and its controlling meansconstitutes a modification -of the form of apparatus shown in Fig. 12 ofsaid pending application, wherein electric motors are employed forraising and lowering the surfac-ing runners. The invention has for itsprincipal objects; the provision of improved controlling means forraising and-lowering the surfacing runners; the provision of meanswhereby the up and down movement of the runnersand the pressure thereofon the glass is automatically controlled byvariations in the currentsupplied to the motors for rotating them, so that the runners riseslightly when the driving-force required rises above a certain point,and whereby the runners lower slightly when the driving force requireddrops below a certain point; and the provision of means whereby thesuccessive runners may be caused to .lift

. from the tables and then return to surfacsheets or from which theglass may Wll'lllg. d1 agram of ing" position in order to skip any tableor tables which-may carry a broken sheet or have been removed for anycause. One embodiment of the invention is illustrated in theaccompanying drawings, wherein:

Figures 1 and 1": grinding machines in side elevation, and the thesystem. Fig. 2 is an enlar' ed vertical sectional view on the line 11- Iof Fig. 1: Fig. 3 is an enlarged sec tion on the line IIIJ-IH ofFig.. 1. And Fig. 4 is an enlarged plan view of the startall controlledfrom a centogether show one of the Application filed August 16, 1927.Serial lio.'2l3,273.

such cars being mounted upon the tracks 5, and moved below the series ofgrinding and polishing machines, by any suitable driving means, such asthat shown in the application referred to and including the racks6.(F1g 1) carried by the under sides of the car bodies and a pinion 6driven from an are carried byspindles 8 driven. by the motors 9 throughsuitable reduction gearing in the casings 10 and 11. The spindle 8 isjournaled in the. housing 12, whose weight and that of the motor,spindle and runner, are carried by the lever 13 pivoted at 14 upon stheframework 15. A link 16, pivoted at:

one end to the framework and at its other end to thehousing 12, servesas a guide for the lower end of the housing. The lever 13 carries at itsinner end the casing 17 and the motor 18. A sleeve 19 is journaled inthe casing and has keyed thereto the worm wheel 20. This worm wheelisdriven from the motor throughthe intermediary of the worm 21 on thecountershaft 22 and thechain 23 passing around the sprockets 24 and 25carried by the motor shaftfand countersha-ft.

Lying below the casing. 17 and supporting it is the carried by t e lever13 upon the trunnions 27. Extending upward through the yikeis the shaft28, whose upper end 29 is square in cross sectionand fits slidingly intothe sleeve 19. The shaft is supported by the antifriction thrust bearing30 resting upon the cross head 31. This cross head is guided verticallby the sides of the yoke 26 and is yielding supported by the spring-32.The lower end of the shaft 28 is threaded through the hub of the spurgear 33 lying in the casing 34 and secured .to the flanges of the beam35 forming a part of the framework 15 by means of bearings 34 and thetrunnions 35. I A' thrust bearing 36 is interposed between the electricmotor (not shown). The runners 7 yoke 26* (Fig. 2), which is itself4:),ing of the relay coil 0,, as later described),

upper side of the hub of the gear and the hub 37 of the casing 34. Thegear 33 may be turned by means of the handle 38 (Fig. 1) secured to theshaft 39, which shaft carries a pinion 40 meshing with the gear 33.. Thelever -13 may thus be raised and lowered by hand, if this becomesnecessary. The handle- 38 may be locked against movement by the pin 41,thus locking the gear 33 against rotation, and under these conditions,the lever 13 may be swung up and down by the operation of the motor 18which rotates the shaft 28 in the hub of the gear 33, such gear thusacting as the nut for securing the longitudinal movement of the shaft28.

The motor 9 is operated by three phase alternating current from thesupply lines 42, 43, and 44, via the lines 45, '46 and 47, which passthrough the control panel 48, as later described, while the motor 18 issupplied with direct current from the supply lines 49 and 50 via thelines 51, 52, and 53, the motor 18 being of the split field type havingthe two field coils 54 and 55, arranged so that, when current flowsthrough the coil 54, the motor is rotated in a direction to lower therunner, and when current flows through the coil 55, the motor is rotatedin a direction to raise the runner.

The section of the field coil of the motor 18, through which the currentflows, is controlled by the contact arm 56 of the watt meter 57. Thiswatt meter is operated from the three phase circuit, which drives themotor 9. When the resistance to the rotation of the runner 7 is just theright amount for which the instrument is set, the arm 56 occupies theneutral position shown, and no current flows through the motor 18 or thecoils 54 or 55. If this resistance becomes less than the desired amount,the arm 56 swings down and engages the contact 58 completing the circuitthrough the motor 18 and coil 54 via the lines 51 and 52, (due to theenergizso that the motor 18 and shaft 28 are rotated to lower the runnerlightly, and so increase the grinding effect an the resistance torotation of the runner. WVhen the resistance is thus increased to thedesired point, the arm 56 is swung up to neutral position again, thusinterrupting the rotatio rof the motor. 011 the other hand, if thegrinding effect becomes greater than the desired amount and the currentflow increases accordingly, the arm 56, swings upward and engages thecontact 59. This completes the circuit through the field coil 55 of themotor via the lines 51, 53, 52 (due to the energizing of the relay coil6, as later described), causing the motor to rotate slightly in adirection to raise the runner and decrease thegrinding pressure on theglass,after which the arm 56 moves back to neutral position again, thusinterrupting the circuit and stopping the motor.

As the watt meter 57, is the same in construction as any commercial Wattmeter, aside from the fact that the contact arm 56 is substituted forthe pointer or indicator on the regulation watt meter,the details ofconstruction of such meter, whereby the arm '56 is swung back and forth,as the flow of current through the runner drive motor 9 varies,depending on the resistance encoun tered by the grinding runner, are notshown vor described. In addition to this watt meter, ;the runner drivemotor circuit 1s provided with another watt meter 60 of regulation .typeprovided with the usual graduations and pointer for indicating theamount of current.

In order to operate the watt meters 57 and matter of economy. Thepotential coil terminals 65 and 66 and 67 and 68 of the meters areconnected to'the lin 61 and the neutral 64 by the lines 69 and 70. Thecurrent coils of the meters have their terminals .71 and 72 and 73 and74 connected to the line 45 of the three phase circuit, which operatesthe runner drive motor 9, as heretofore referred to. I

The coils a and b of the relays (heretofore referred to as energizedwhen the arm 56 swings down and uprespectively), serve to move thecontact bars 75 and 76 up so that they engage and connect the contacts77, 77 and 78, 78. The current for this purpose is supplied from theline 49 and when the arm 56 is in down position, the circuit energizingthe coil a is as follows: line 51, coil (1, arm 56, line 52, switch 0,line 52, switches in and i, line 52, switch 94, line 52", line 52,switch it and line 52. \Vhen the arm 56 is in up position, the circuitenergizing the coil 6 is as follows: line 51, coil 5, arm 56, and line52, etc. as just above stated. In order to short circuit the wattmeters, when the runner is in its upper most position, and the motor 9is being started, the-switch ais provided in the circuit 45. This switchis normally held open by the spring 79, but is closed on the downwardmovement of the lever 13, which engages a stop 80 on the connection 81,such connection being secured ,-'to a crank arm carriedby the switcharm.

This protects the meters from the overload incident to the starting ofthe motors. A companion switch f similar to the switch 6 is similarlyoperated by the movement of the lever 13 for a purpose, as laterexplained.

T he up and down movement of the runner,

may be controlled by hand from the switches k and 2', operatingin-conjunction with the starting panel 48, or may be controlled from apoint remote from the machine by direct current from the line 82,whichreturns to the negative line 50 via the line 52 inconjuncheretofore referred to, from which point all the bar to theright, closes the relay arms of the grinding and polishing machines arecontrolled. This station includes a sequence panel, which regulates intimed relation the application of current first to the line 86 tooperate the relay 84, and then to theline 82 and the starter panel 48.

The starter'panel comprises the solenoid bar 87, yielding ly held to theleft by the spring 88, but movable to the right by the energizing of thecoil 89. The movement of 90, 91, 92and 93, and opensone arm ofv theswitch 94 while closing the other. The members 95, 95, 95 arethermo-relay switches well known in the art, which open the controlcircuits 96 and 97 in case of an overload in the circuits 45, 46, 47 andthus protect the motor. When current is supplied through the line 85 tothe coil 98 of the relay 84, the arm'99 is closed, and current flows tothe coil 89 of the starter 48 from the line 82 via the line 96, startbutton g, line 100, arm 99, line 101, line 102, switch arm *f and line103. The return circuit from the coil 89 to the" negative line 50,comprises the line 97 the hand safety switch it, and the line 52.

This causes the\bar 87 to move to theright,

closing the arms 90, 91,92 and 93, and opening the upper arm of-th'eswitch 94 and closing the other-arm.- The'closing of the arms 90, 91 and93 completes the circuits 45, 4e and 47 of the motor 9, so that'it'starts rotating.

The motor 18 is also started rotating. as soon as current is supplied tothe" motor 9, as the arm 56 of the watt meter 57 is at this time in itslower position engaging the contact 58, and direct current from the line.51,

therefore, flows through the 'coil a and contact arm -56, returning tothe negative line 50 via the switch 0, line 52, switch switch '5, line52, switch arm 94, line 52", switch h and line 52. The closing ofcontact bar 75, thus completes the circuit through the motor 18, and thedownfield coil 54, via the line 51, line 52, switch j, line 52, barf75,line 52, switch 0, line 52, switches 7c and i, line'52, etc.,- as justdescribed. The runner, therefore, starts to move down and keeps onmoving until it engages the glass and the pressure is increased so thatthe current requirement for driving it causes the arm 56 of thev wattmeter 57 to move to the'neutral position shown, thus interrupting thecircuit through the motor 18. and its down feed coil 54.

The operation of the starter panel 48 by the coil 89 also closes aholding circuit through the coil 89, which is maintained after the relay84 opens, and interrupts the circuit 103. The opening of the arm 99 ofthe relay 84 occurs-when current through the coil 98 from the circuit 85is discontinued, such interru tion occuring at the sequence panel heretoore mentioned, almost immediately after the energizingof the coil 89.

This holding circuit between the lines 49 and 50 and through the coil89, comprises the line 96, button g, line '96, arm 92, line 105, coil89, line 97, switch It and 1111s 52.-- N

This circuit may be interruptedto stop the motor 9 by-pressing thebutton g andmay be started again by pressing the button Z} The motor '18may also be started to move the runner up by pressing the button-k,which completes the circuit comprising the line 51,

.motor 18and its field coil 55, line 53, limit switch m, line 53, line53, contact bar of button 70,- line 52, switch it, and line 52.,- Theswitch 7 also lies in the circuit 96, 102, 103 which energizes the coil89 closing the starter relay'48, and this switch is "closed when therunner is in up position and open when it is in down position. Thisinsures. that the starter relay cannot be closed, and the rotation ofthe runner started in any position, except the upper position, for thereason set forth in my pending application heretofore referred to.

In order to prevent the runner from ever striking the table beneath it,the limit switch y is provided operated from the rod .106 pivotallyconnected to the lever 13. The opening of this switch interrupts thecircuit 52.past the down field coil 54. Similarly, the limit switch m isopened by the rod 106 interrupting the circuit through the up field coil55, when the runner reaches the proper I upper extreme limit ofmovement.

As heretofore indicated, the arm 56 of the watt meter 57 regulates thevertical position, of the runner and its pressure, and rinding effect onthe glass beneath it. TVhen the drag of theTrunner'increases beyond apredetermined point, the-current increase is such that the arm 56 swingsup and engages the contact 59, causing the relay 76 to close andcompleting the circuit 52 through the up field coil 55 of the motor 18,and such motor-makes a few turns to move the runner up, thus reducingthe pressure on the glass, so'that; the driving current is reduced andthe arm 56 swings back to the neutral shown. When the drag between therunner andglass decreases beyond a predete'rmined amount, the'currentdrop is registered by the downward movement of the arm 56 until itengages the contact 58, causing the energizing of the relay a, so thatit closes, thus completing the circuit through the down field coil 54 ofthe motor 18, via the circuits 53, 52. The motor 18 then rotates a fewturns causing the downward movement of the runner until the drag.reaches a point where the current requirement moves the arm 56 up toneutral position again. 7

The switches 0 come into play when it becomes desirable, to have all ofthe runners raise and lower, one after the other, to permit the passageof a table carrying cracked or broken glass, or one from which the glasshas been removed. The switch is of the four pole type, adapted toconnect the contacts 107 and 108 when in the position shown, and whenrotated 180 degrees, to connect the contacts 109 and 110. His operatedby the arm 111 pivoted at 112 and connected to the movable part ofthe'switeh by the chain 113. After the arm has "been swung to the rightto rotate the switch 180 degrees, it is returned again to the positionshown by the spring 114. The switch includes a ratchet or clutch forpermitting this operation, on

the order of the ordinary pull chain light socket, and is so well knownin the art that its details are not shown. The tables or cars; 2, 3,4,etc. are each provided with a pair of tripping devices at the endsthereof adapted to engage the arm 111 controlling the switch. Thesedevices include brackets 115 secured to the table and provided with theremovable pins 116. These pins are adapted to engage the arm 111 andswing it laterally to-move the switch from one position to the otherposition.

If table 2 has on it a sheet of broken glass which it is desired thegrinder and polisher runners shall all skip, the pins 116 are placed inposition in the brackets 115 at each end of the table. When the forwardpin strikes the handle 111 of the switch 0, the switch is shifted180degrees, so that the switch arm engages and conencts the contacts109, 110. This completes the circuit through the up coil 55, suchcircuit comprising the line 51, motor 18 and coil 55, switch m, line-53,switch 0, line 52, switches 7." and 2', line 52, switch 94, line 52",switch it, and line 52. The motor 18, therefore,'rotates to lift therunner, and this movement continues until the table- 2 passes beneaththe runner and the second pin 116 engages the handle of i the switch aand moves it to shift the switch back to the position shown,interrupting the circuit through the up coil 55 of the motor *andcompleting a circuit through the down coil 54. At this time, the arm 56of thewatt meter 57 engages the contact 58, since there is no load onthe motor 9, so that the of a runner mounted for rotation above thetable and movable vertically, an electric motor for rotating the runner,a second electric motor and connections arranged to raise and lower therunner, and means controlled by the current supplied to the first motorfor controlling the direction of rotation of the second motor.

2. The combination with a surfacing table, of a runner mounted forrotation above the table and movable vertically, an electric motor forrotating the runner, a second elec-' tric motor and connections arrangedto raise and lower the runner, means for reversing the direction ofrotation of the second motor, and means controlled by the currentsupplied to the first motor for controlling said reversing means.

3. The combination with a surfacing table, of a runner mounted forrotation above the table and movable vertically, an electric motor forrotating the runner, a second electric motor and connections arranged toraise and lower the runner, and a. contact making watt meter controlledby the current which operates the first motor for controlling thedirection of rotation of the sec- 0nd motor.

4. The combination with a surfacing table,

of a runner mounted for rotation above the table and movable vertically,an electric motor for rotating'the runner, a second elecraise and lowerthe runner, and meanscon trolledby the current for operating the firstmotor for controlling the direction of rotation of said second motor byshifting the flow of operating current to such motor from one portion ofsaid split field to another portion thereof.

6. The combination with a surfacing table, of a runner mounted forrotation above the table and movable vertically, an electric motor forrotating the runner, a second. split field motor and connectionsarranged to raise and lower the runner, depending upon which part of thefield receives the operating current to the motor, and means controlledby the current for operatin the first motor and including a contact mang watt meter, for governing the application of the operating current tosaid parts of said split field, and in this manner controlling thedirection "of rotation of said second motor 7 The combination with asurfacing ta-" ble, of a runnermoulited for rotationabove the table and.movable vertically, an electric motor for rotating the runner, a secondsplit field motor and connections arranged to raise and lower therunner, depending upon which part of the field receives the operatingcurrent to the motor, and means controlled by the current for operatinthe first motor and including a contact ma ing watt meter, and a pair ofrelays for governing the application of the operating current to sa dparts of said split field, and in this manner controlling the directionof rotation of said second motor.

8. The combination with a surfacing table, of a runner mounted forrotation above the table, and" movable vertically, an electric motor forrotating the runner, a second electric motor and connections arranged toraise and lower the runner,,means controlled by the current supplied tothe firstmotor for controlling the direction oi rotatlon of the secondmotor and a limit switch controlling the flow-of current to said secondmotor and arranged to be opened by the downward controlling thedirection of rotation of the second motor and limit switches controllingthe flow of current to said second motor and" arranged to be opened bythe up and down? movement of the runner when such runner reaches certainpredetermined levels.

10. In' apparatus .for continuously surfacing sheets of material, aseries of surfacing machines, each having a vertically movable drivenrunner, a prime mover for lifting each runner,'suporting means forcarrying a series of sheets of. material continuously beneath therunners, a series of control v continuously beneath the runners, apluraldevices arranged along the line of movement of said supportingmeans, and a series of actuating abutments for operating saidcontrol.devices carried by said supporting means and adapted to bepositioned so as to operate said devices, or to avoid operating them,the said control devices being arranged to gov-.

able driven runner, an electrically controlled prime mover for liftingeach runner, a supporting train of cars or tables for carrying a seriesof sheets of material continuously beneath the runners, aiplurality ofswitchesfor controlling the application of electric current to securethe actuation of said prime movers, arranged in series along theline oftravel of said train, and switch actuating abutments arranged in seriesalong the train, and adapted to be positioned to operate said switchesor to avoid operating them, the said switches being arranged to governthe application of power to said prime movers, so that the series ofrunners may be raised and lowered successivelyto permit any desiredsection of the train to pass beneath runners without being" engagedthereby.

1 12. In apparatus for continuously surfacing sheets of material, aseries of surfacing machines, each having a vertically movable drivenrunner, an electric motor and connections for moving each of the runnersup and down, a supporting train of cars or tables for carrying a seriesof sheets o'fmaterial continuously'beneath the runners, a plurality ofswitches for controlling the application of electric current to securethe acutation of said motors arranged in series along the line of travelof said train, and switch actuating abutments arranged in series alongthe'train 'and adapted to be positioned to operate said switches or toavoid operating them, the said switches being arranged to govern theflow of current to said, motors, in one position directing the currentso as to cause the motors to lower the runners, and in another positiondirecting the current so as to cause the motors to lower the runners.

" 1 3. In apparatus for continuously surfacing sheets o'fmaterial, aseries of surfacing machines, each having a vertically movable drivenrunner, an electric split field motor and connections for moving eachrunner up and down depending upon which of the coils of the split fieldis supplied with operating current, a supporting. train of cars ortables for carrying a series of sheets of'material ity of switches forcontrollying the application of electric current to said motors,arranged in seriesalong the line of travel of the train, and switchactuating .abutments arranged in series along the train and adapted tobe positioned, either to operate said switches or to avoid operatingthem, each of said switches being arranged so that in one position itdirects the'current through one of the field coils of the split fieldmotor 5 to cause the motor to rotate so as to lower the runner and-sothat in another position it directs the current through the other of thefield coils of the motor to cause the motor to rotate in the reversedirection so as to raise the runner.

In testimony whereof, I have hereunto subscribed my name this 9th day ofAug.,

ALFRED L. HARRINGTON.

